The objectives of this proposed project are as follows: (1) To verify the number of RNA polymerase binding sites (promoter sites) on bacteriophage lambda and T7 DNA; to isolate the DNA segments corresponding to the promoter sites and then to determine their size and nucleotide sequence. The methods developed in our laboratory will be used for DNA sequence analysis. (2) To isolate repressor binding sites (operators) of lac DNA, and to determine their size and nucleotide sequence. (3) To develop improved methods for DNA sequence analysis so that the objectives listed above can be achieved more readily.